/Engine/Source/Editor/ContentBrowserData/Public/ContentBrowserDataSource.h
This duplicates the items at their current paths and assigns them a default unique name.
True if any items were duplicated, false otherwise.
virtual bool BulkDuplicateItems ( [TArrayView](API\Runtime\Core\Containers\TArrayView)< const [FContentBrowserItemData](API\Editor\ContentBrowserData\FContentBrowserItemData) > InItems, [TArray](API\Runtime\Core\Containers\TArray)< [FContentBrowserItemData](API\Editor\ContentBrowserData\FContentBrowserItemData) > & OutNewItems )